Have your thyroid levels been tested? Those are some classic symptoms of hyperthyroid (inability to gain weight on massive calories, feeling hot, sweating, fidgeting). While it’s “nice” in being able to eat whatever you want, it’s hell on your body and can lead to ugly complications down the road if it’s not treated.
Like what? Just curious.
Heart problems, including atrial fibrillation and congestive heart failure, osteoporosis, eye problems, including bulging eyes (in a form of hyperthyroidism called Graves’ Disease), dry eyes, loss of vision and most seriously, thyrotoxic crisis, also known as thyroid storm, when your everyday symptoms get turned up to 11 and your body just burns itself out very, very quickly, with fever, rapid heart rate, dehydration, vomiting, delirium and coma on the way. Thyrotoxic crisis can be deadly within hours without intensive medical intervention.
I’ve had a full thyroid panel a few times and always tested normal. Due to poor nutrition I used to have a lot of hypo-, not hyper-, symptoms - hair loss, freezing extremities, low overall body temp (which I still have - 97 degrees), low energy, slow pulse. Thankfully I don’t anymore since I’ve changed my diet.
Homer Simpson flashback to high school days…
“Gee Homer - how can you eat so much and not get fat?”
“It must be my metabolism…” [Combs his Elvis haircut and looks at a huge chunk left in the comb] “Oh well, there’s lots more where that came from.”
What explains morbid obesity? These people keep eating and their health goes to hell. It cannot be pleasant to weigh 500 pounds…yet their brains keep telling their bodies to keep eating-clearly some limiting mechanism is being overidden, in the metabolism of these people.Another question: people who have been starved for years (like the Nazi death camp inmates)-once they get out into normal society, do the begin eating to excess, or do the go back to their normal weights and stay that way?
Although I trust that the math works out, something that strikes me as a tad facile about this view is that it would lead us to expect just as many people unknowingly undereating 100 calories per day and losing ten pounds a year. But in my experience of the world, the overwhelming trend is toward gaining weight rather than losing weight over time. What accounts for this asymmetry? Is it simply that eating more is more pleasurable than eating less?
Or to recast the OP’s question: Why do some people (effortlessly) get fat and others (effortlessly) don’t, but nobody seems to get thin without putting forth significant effort?
AIUI, it’s a myth that basal metabolic rate tends to decrease with age, or at least that age in itself tends to cause it to decrease, and then you get fat. It’s more like the other way round - you get fat and lose muscle due to lifestyle changes, infirmity, and very gradual weight gain in adulthood finally catching up on you. And less muscle means a lower metabolic rate, but people tend not to decrease their calorie consumption from what they’re used to.
Yes, I was able to maintain just 10-15 extra pounds until I started taking insulin. Now I’ve been gaining about 2 pounds/month. Many people on insulin report weight gain.
Much as we all find it easier to be simplistic and say that it’s calories in minus calories expended that determines whether or not someone is fat, it just doesn’t work that way. Humans are complex machines. Sure, if you fidget a lot, you may burn a total of a few hundred calories a day more than you would otherwise, and for some people, that explains why they don’t gain weight. A physically demanding job may make the difference for some people. But the rate at which we burn up calories can vary a great deal from individual to individual. Period.
I am a 5’3" woman. When I was in college, I weighed 100 pounds. I ate well over 2500 calories a day. My only exercise was walking to classes–which on some days amounted to a total of perhaps 2 miles. I wanted to get up to 105 pounds so that I could donate blood. (They wouldn’t let you donate unless you hit the minimum weight.) My roommate volunteered to help me gain the weight. For a week, we ate exactly the same things in the same portions–all our food was from the dining hall, and we ate all our meals together–except that she had me drinking two milkshakes a day. At the end of the week, she had gained a couple of pounds, and I weighed…100 pounds.
Now that I’m in my 50’s, it no longer works that way. I engage in vigorous aerobic exercise daily: every other day, I burn off about 500 calories exercising at the gym; on alternate days, I burn off about 300 calories plus lift weights. I count calories very carefully, because if I exceed about 1700 calories per day, I gain weight. No, I don’t cheat, increase portions, or overestimate the number of calories I take in. Believe me, I’d love it if that were the case. I just have to be very careful to eat less than what most people can consume to maintain their weight, or I gain. My thyroid functions normally. It’s just the way my body works.
I think it’s probably easiest to subscribe to the “It’s just a matter of a simple equation” theory if you’re naturally thin or at least have a normal metabolism. Or maybe if you’re a black-and-white thinker.
Kudos to the OP for deciding to get some healthy exercise. I hope you’re able to eat those vast quantities of food when you’re in your fifties and sixties. I live vicariously! 
In my experience, there are two reasons. One is that some people who would lose weight effortlessly actually put effort into *not *losing weight ( and I know a few) . Another is that some people do lose weight pretty effortlessly, at least sometimes. For example, when I am very busy or stressed, I tend to eat less. I’ m not trying to eat less, I just don’t have the time to eat and have less of an appetite. If people notice I’ve lost weight, I don’t go into a whole story about how I didn’t actually mean to lose weight, but I unknowingly started eating “x” fewer calories per day and the weight dropped off. I just say “thank you”.
I don’t know if anyone really knows for sure. The reality is if we understood the anatomy/physiology of obesity with a high degree of certainty we would probaby have effective treatments for it. As it is, the only treatments that work long term are surgery and even those can be unreliable.
So bodyweight comes down to various physiological factors, and I guess yours predispose you to being thin.
The whole ‘calories in/calories out’ equation is really not all that simple. There are dozens of factors that go into it outside of that. Plus a calorie of casein protein is not the same as a calorie of sugar.
But less muscle mass with aging is not exclusively a consequence of less exercise (albeit more resistance exercise can offset it). It is called sarcopenia.
Muscle mass, or more accurately, fat free mass, is the prime determinate of BMR. It takes more work, more explicit resistance work, and more quality protein, to maintain or to increase muscle mass gets older.
In fact, some diabetics (most notably teen girls) deliberately underdose with insulin to lose weight. It’s a well-known problem.
Not exclusively a consequence of less exercise, but mostly, it seems to be saying. But I take your point that your link does suggest some loss of muscle mass, and consequent decrease in BMR, that can be attributed fairly directly to age. How much BMR decrease is not clear.
That’s so disturbing . . . hyperglycemia is sooo bad for your body. As a former teenage girl myself, I have to say, they are teh dubm.
Yes, some portion, perhaps even most, of the muscle mass loss associated with aging can be the result of less resistance type activity (such as heavy physical labor). And some is the result of other changes that occur with aging, like age related death of motor neurons (which then no longer send their local growth factors into the muscles), slower protein synthesis in muscles possibly related to a decreasing population of the satellite cells that support muscle growth, and changing hormone levels (less Growth hormone, testosterone, and IGF).
BMR is, as per my cite in my first post, 3/4ths correlated with lean body mass; a loss of lean body mass (often also called “fat free mass”) will certainly decrease BMR, and without a decrease in intake and/or without an increase in energy expended, cause an increase in fat mass.
That’s why middle aged folk like me are really well advised to focus a bit more on resistance exercise as opposed to exclusively aerobic work-outs as we age even if we merely want to maintain our current muscle mass and fitness level. Just doing the same thing as before will not give the same results as before.
While we’re talking diabetes, I have to say that, George, that diet sounds like a recipe for Type 2. Even if you’re not gaining weight, it’s not doing you any good.
I write this as someone who also eats loads of crap and doesn’t gain weight, BTW, but do as I say not as I do…
(I do at least do quite a lot of exercise, and need about 3500 calories a day just to maintain my weight. I’m 33 and male, and no doubt I’ll start to see the spread soon…)
Heart disease, diabetes and other chronic diseases are quite common in slender people, and IMO it’s because so many of us think that as long as we aren’t fat, we’re ‘healthy’ even living vastly unhealthy lifestyles. Often someone who is congenitally thin won’t get a wake-up call in the form of weight gain before they discover they have made themselves sick.
George, it’s good your BP is on the low side, but low total cholesterol isn’t so good if you look at the latest research. I’m trying to get mine up, as it’s consistently under 160. Cancers of all kinds and depression/anxiety have been found to be much more common in people with low cholesterol. It’s also important to look at your ratios, which your doctor should have on file. With your diet, I suspect you have relatively high triglycerides and low HDL. No matter the total numbers, the ratios between all these factors are much better at predicting your chances of suffering from heart disease, etc.
Someone one should mention to them that the average human foot weighs about 2 lbs. If you have both of them amputated you can permanently lose up to 4 lbs. What with urinary incontinence, she need never worry about excess water weight, either. Seriously, diabetic neuropathy is no joke.
I don’t see how anything you wrote here contradicts the rather basic, but easily understood “calories in - calories out = weight control” model. Your body is a reactor; the calories we take in are the fuel that powers the reactor. The energy your body expends, even at rest, represents the calories out. If you take in more fuel than your body can use, you’ll store it for later in the form of fat (cold storage fuel). If your reactor works efficiently and you’re taking on clean fuel (normal or high metabolism with no barriers to absorption and processing), you’ll expend energy more efficiently and will produce less waste and will store less fuel in the form of fat. When your reactor works less efficiently and/or takes on fuel it can’t use (i.e., excessive carbohydrates, fats or proteins), those extraneous nutrients are either expelled unused or stored for later need in the form of fat.
Your 20 year old reactor is not going to be as efficient as your 57 year old reactor. The aging process is the body breaking down. Like you said, it’s a machine and it’s not going to last forever or even work as good as when it was newer. Ergo, it’s no surprise that even with maybe 7000 more calories introduced into your diet for a week, your 20 yr old body was able to temporarily adjust metabolic rate to process those calories. Just because now 7000 more calories might net you a couple of pounds at your current level of activity and metabolic rate, doesn’t mean that the formula is any more or less complicated than it was at 20. It’s just your reactor is less efficient.